The objective of this project is to develop, evaluate, and report the methodology and results for generation and monitoring techniques necessary for conducting prechronic inhalation studies with 2-butoxyethanol. In addition, the contractor will characterize dose-response relationships and toxicity of 2-butoxyethanol administered by inhalation to rats and mice in 14-day repeated-dose, 90-day subchronic and 2-year chronic studies. Animals will be exposed for 6 hours per day, 5 days per week for 14 and 90 days or 2 years. At the end of each study, all animals will be given gross and microscopic histopathologic evaluations. Hematology will be performed at the 90-day study sacrifice. The results of each study will be used by NTP to establish doses to be used in the next study (i.e., the 14-day results for the 90-day study; the 90-day results for the chronic study).